ethdb: Implement interface for prefixed operations to the DB (#3536)

This commit is contained in:
Nick Johnson 2017-01-11 12:26:09 +00:00 committed by Felix Lange
parent 8820d97039
commit d30d7800e0
1 changed files with 52 additions and 0 deletions

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@ -305,3 +305,55 @@ func (b *ldbBatch) Put(key, value []byte) error {
func (b *ldbBatch) Write() error { func (b *ldbBatch) Write() error {
return b.db.Write(b.b, nil) return b.db.Write(b.b, nil)
} }
type table struct {
db Database
prefix string
}
// NewTable returns a Database object that prefixes all keys with a given
// string.
func NewTable(db Database, prefix string) Database {
return &table{
db: db,
prefix: prefix,
}
}
func (dt *table) Put(key []byte, value []byte) error {
return dt.db.Put(append([]byte(dt.prefix), key...), value)
}
func (dt *table) Get(key []byte) ([]byte, error) {
return dt.db.Get(append([]byte(dt.prefix), key...))
}
func (dt *table) Delete(key []byte) error {
return dt.db.Delete(append([]byte(dt.prefix), key...))
}
func (dt *table) Close() {
// Do nothing; don't close the underlying DB.
}
type tableBatch struct {
batch Batch
prefix string
}
// NewTableBatch returns a Batch object which prefixes all keys with a given string.
func NewTableBatch(db Database, prefix string) Batch {
return &tableBatch{db.NewBatch(), prefix}
}
func (dt *table) NewBatch() Batch {
return &tableBatch{dt.db.NewBatch(), dt.prefix}
}
func (tb *tableBatch) Put(key, value []byte) error {
return tb.batch.Put(append([]byte(tb.prefix), key...), value)
}
func (tb *tableBatch) Write() error {
return tb.batch.Write()
}